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Elevation.
Set. Pour.
This stake was placed by a licensed Professional Engineer. It marks the exact elevation your formwork needs to hit.
TideMark is an elevation reference tool — not a boundary, topographic, or construction survey.
It’s already set.
Just tie your line.
A TideMark is an elevation reference stake installed at a surveyed location and locked to a specific height. The lock screw marks your target Finished Floor Elevation. Thread the eye bolt, tie your stringline, and set forms to that line. Your project’s PE-stamped TideMark exhibit has the full details.
How to use it
Locate all stakes
Find every TideMark on site using the exhibit site plan. Confirm each one is upright and undisturbed.
Attach the eye bolt
Remove the cap and thread the eye bolt into the top of the tower.
Tie your stringline
Run your string through the eye bolt. The stake is already set to the correct FFE — no measuring needed.
Set forms to the line
Align the top of your formwork with the stringline. That’s your finished floor elevation.
Photograph everything
Photo each stake showing the lock position, a tape measurement to top of form, and an overall shot of the formwork.
Send for verification
Send photos to the engineer. Do not pour until you receive written clearance.
Do not disturb the stakes.
Do not move, pull, re-drive, or relocate any TideMark stake.
Do not adjust or loosen the lock screw. It was set by the engineer.
Do not use a stake that’s been hit by equipment, tilted, or pulled out.
Do not pour concrete without photo verification from the engineer.
If a stake has been disturbed in any way, stop and call the engineer before proceeding. Their contact information is on your TideMark exhibit.
What’s in a TideMark?
Every TideMark comes with a PE-stamped elevation exhibit — the document that tells your crew what the stakes mean and how to use them.
Target elevation
The exact Finished Floor Elevation your slab needs to hit, referenced to NAVD88.
Stake locations
Site plan showing where every TideMark was installed and what each offset means.
Photo references
Annotated photographs of each installed stake so you can confirm you’re at the right one.
Verification protocol
What photos to take, who to send them to, and what to do before you pour.
It’s a reference tool — not a survey. You’re still responsible for verifying field conditions match the exhibit.
Elevation. Established.
Stakes installed. Done.
We visit your site, perform a differential elevation observation, install TideMark stakes set to your required FFE, and deliver a PE-stamped exhibit. Your contractor shows up to stakes that are ready to use.
813-694-8989 Order a TideMark or contact us with questionsTideMark is open source.
Hardware designs, field guides, and documentation — all on GitHub. Print your own. Modify the design. Contribute improvements.
View on GitHub